After reading these posts, I now realize that my little girl is completely normal. She will charge forward on her leash, pulling as hard as she can, sniffing everything. Then, after a short walk, she is tired and needs me to carry her for a while. Sometimes she just slows down, but her nose is constantly on the ground. She too doesn't care is she is choking. One problem that we have is that she wants to attack every dog she sees if she is on a leash. If we take her to the dog park or in a yard with other dogs and not have her on a leash, she is very shy. Does anyone else notice this about their Yorkie babies?